The subject matter described herein relates generally to powered rail vehicles.
Known railway systems include powered rail vehicles that travel along one or more rails of a track. The powered rail vehicles include motors that provide the tractive effort that propels the rail vehicles along the track. In one mode of operation, the motors are powered by electric current. In some known rail vehicles, the electric current is obtained from an on-board prime mover. For example, the electric current may be created by an alternator or generator that is coupled to a shaft of an engine. The engine consumes a fuel, such as diesel fuel, gas fuel, and the like, to generate movement of the shaft. The movement of the shaft is converted into electrical current by the alternator or generator. This current is fed to the motor to propel the rail vehicle along the track.
In some other known powered rail vehicles, the rail vehicles are electrified rail vehicles that receive electric current from an external source located outside of the rail vehicle. For example, the rail vehicles may be electrified locomotives that receive electric current from a catenary wire located above the track or from an electrified rail near the track. The electric current is received from the catenary or electrified rail and is supplied to the motor. The motor is powered by the current to propel the rail vehicle along the track.
Electrified rail vehicles have advantages over rail vehicles with on-board prime movers. For example, the electrified rail vehicles may have a higher power-to-weight ratio than rail vehicles with on-board prime movers. The electrified rail vehicles may be capable of faster acceleration and greater tractive effort on relatively steep grades than other rail vehicles. Electrified rail vehicles may produce less exhaust fumes and carbon emissions and produce less acoustic noise than other rail vehicles, such as rail vehicles powered by diesel engines. Additionally, electrified rail vehicles may be able to create regenerative current when the rail vehicles brake, which can be supplied back to a utility power grid.
A significant amount of the total length of tracks in various countries is not electrified. For example, many tracks may not include a catenary or electrified rail to power electrified rail vehicles. As a result, most of the tracks are traveled only by rail vehicles having on-board prime movers. Due to the benefits achieved with electrified rail vehicles, there is considerable interest in transitioning more tracks and rail vehicles to electrified tracks and electrified rail vehicles. The cost of converting the tracks to enable electrified rail vehicles to travel thereon is considerable. As a result, the transition of a track from a non-electrified track to an electrified track can be very expensive and slow. In some locations, only portions of the tracks are capable of handling electrified rail vehicles while other portions are incapable of supplying current to the electrified rail vehicles. While there currently is significant interest in converting more of the tracks to tracks capable of providing current to the electrified rail vehicles, given the large expense and time involved in converting the tracks, it is difficult to know when a given length of track will be capable of handling electrified rail vehicles. As a result, some known rail vehicles are limited as to which portions of the tracks that the rail vehicles may travel on.
A need exists for rail vehicles that are capable of migrating or adapting from a configuration where the rail vehicles travel along non-electrified tracks to a configuration where the rail vehicles are capable of travelling along electrified tracks.